The biology common to all projects in gene therapy involves the use of safe and efficient gene transfer vectors. The goal of the Vector Core is to provide to University of Pennsylvania investigators the reagents, know-how and services in the area of vectors. This Core has established a list of standard services in the design, creation, production and evaluation of a variety of vector systems. An array of services from vector cloning to large-scale production of viral stocks is available for murine-based retroviruses, adenoviruses and adeno-associated viruses (AAV). Exhaustive quality control analysis of vector lots is available in the Vector Core. Services of the Core range from acquisition of necessary reagents to training of graduate students and postdoctoral fellows, to more complete services in which the end product is large-scale preparation of the purified recombinant vector. The Vector Core has been essential to Penn investigators. Much of the technology developed in Dr. Wilson's laboratory is transferred to the Vector Core soon after it undergoes initial characterization. The Vector Core mobilizes to further evaluate new vector systems and establishes standard operating procedures for the creation of new recombinants and large-scale production. Once this is achieved, the vector is then distributed to the faculty of the University of Pennsylvania for use in their specific research projects.